Eugene schneider



CROSS REFERENCE June 16, 1925. l Lgl SCHNEIDER APPARATUS FOR ASC'JHTAINING vTHE ALTITUDE op AERIAL TARGETS Filed March 14, 1923 2 Sheets-Sheet l Egal Fig@ 40 m SEARCH ROOM' Jun@ 16, 192s. v'11,542,53f4

E. SCHNEIDER APPARATUS FOR ASCERTAINING THE ALTITUDE 0F AERIAL TRGETS Filed MIOh 14' 1925 2 Sheets-Sheet ,2

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Patented June 16, 1925.` A `i narran stares earearr erraten.v

EUGNE SCHNEIDER, OF PARIS. FRANCE. ASSIGNOR TO SCHNEIDER 85 GIE., OF PARIS, FRANCE, A LMITED JOINT-STOCK COMPANY OF FRANCE.

APPARATUS FOR ASCERTAINING THE ALTITUDE OF AERIAL TAEG-ETS.

Application filed March 14, 1923. Serial No. 625,042.

T all whom if may con-cern:

Be it known that L EUGEXE SCHNEIDER, a citizen of the Republic of France, residing at Paris, F rance, have invented new and useful Improvements in Apparatus for Ascertaining the Altitude ot Aerial Targets, which invention is fully set forth in the following specification.

In ring upon an aerial target air-ship or aeroplane), when using an apparatus known under the name of' corrector of the type described in Patent No. 1.345.697. itis necessur)7 to be able to ascertain the altitude, assumed to be constant, at which the enemy is lving.

The present. invention has for its object to provide improved apparatus for ascertainine` directly the altitude ot the aerial target by the use of a monostatic telemeter which ma)v be of anyv suitable type.

lt comprises broadly the combination, with a monostatic telemeter of an apparatus actuated for instance, bv an auxiliary operator as a function ot the site angle of the target. This simple actuation eects autornaticallyv the adjustment ot the said telemeter: in other words, the combination which is the object ot this invention relieves the telemeter operator of the necessiti7 ot constantljv adjusting the telemeter. which operation is almost impossible in the case of a target so mobile as an airship or aeroplane. In a word, this invention a'ords the very greatadvantageof simplifying considerablj7 t-be service of t-he telemeter operator who becomes in reality an altimeter operator1 and needs no longer to interveneI` eX- cept in the exce )tional casewhere the target changes its altitude.

40' In the accompanying drawings The diagrammatic Figure 1 which is given by wav or example onlv. illustrates a constructional torni of an improved mechanism for maintaininf r automaticalljv the adjust- 15 ment or the telemeter as a function ot the site angle oi' the aerial target.

Figure illustrates a general arrangement et' the nrreroved apparatus (the telineter and automatic l adjusting mechanism combined) assumed to be viewed from the direction ot the altimeter operator.

Figure 3 isa view of a general arrangement of the improved apparatus viewed by an observer situated at the righthand of the altimeter operator.

Figure 4 is a general view of the improved apparatus assumed to be viewed from the direction ot the auxiliary operator.

Figures 5 and 6 illustrate modifications of the .improved apparatus shown in Figure l.

The diae'rai'rimatic Figure 7 illustrates a constructional detail.

lt D is the distance ot the aerial target, H its altitude. and a its site angle, we have then between these three magnitudes the relation where K1 is a constant.

It in equation (2), D be replaced by its value (l), we get z- Assuming that a lilheatstone bridge (F l) is constituted with three arms having respectively the ohmic resistance K2- sin sf.; K3 l-l: and lili then thev resistance S 'which must be introduced into the' fourth arm for bringing the pointer of the voltiueter V back to zero, will be given by the lforinula sin a ign l On comparingV this with equation (3), it

will be seen that :esis (5) liz-K4 This eilsuution shows that the nuiulier of revolutions fn which must be `given to the knob ot the telenieter in order to maintain its adjustment, is proiiortional to the re sistance S ot' the fourth arni ot the bridge. This. adjustment can then be effected very simplyv and continuously by actuatingT the knob ofthe teleineter by lmeans ot' the screw u2 which serves to drive the contact c'.

In order to reduce the number of opera tors to a minimum, as Well as to simplify the construction, the rlieostat which introduces automatically the resistance K2 sin oi is preferably mounted on the correcting apparatus (not shown)v from which the indication ofthe site. angle is taken.

The rlieostats giving SLK? H and K4 are mounted in a special casing C (Figs. 2, 3 and il which contains likewise the' voltnie ter "vl and i'hc fixed' resistance K5 l) design-ed to limit the current supplied by the battery P'.

The movable Contact c of the rheostat which `gives S, is shifted tor instance by an auxiliary operator entrusted with the' duty of keeping' the pointer ot' the voltnieter V on zero. This shitting is produced b v means of the crank nl, screw o2 and nut u?. The screw lu? is connected tor instance, by means of a liexilile shaft F to the adjusting` knob a4 of the telenieter.

The movable contact f of the rheostat that gives l): H, is shifted by the. telenieter operator. This shifti v. is eii'ected b v means of the crank ai, screw l2v2 and nut o3. The duties oi the teleinetei operator are thus reduced to the much simpler duties ot analtiinetcr operator.

It is to he noted thatthe operation ot the gunner actuating' the site angle mechanism and the operation ot the altinieter operator are entirely independent of each other, and do not atleet or react in an;v Way upon each other: this is one ot the essential advantages of the improved apparatus.

In die construction oi' the rheostat. which is to give iii., sin cf. the most simple means of olitainiimg tie siniisoi-lal variation ol the i' in shifting proiioitionall)v to the anide :1. a movable contact of a rheistiit cfuistiti "ed hv a iiiile'coiietl ivijli contacting turns around a strip oi insulating material having a cosiniisoidal Qroiile.

A ssuniing in inact -"ii'iitiii" a'lgs't'rip (which is assumed at' firstto have' no thickresistance consists ness Whatever) limited by the contour O A M B O (Fiez) dehned by the straight.

lines (v) A and vO B and the curve B M A which corresponds to the equation*- there is ivound a Very line insulated wire havingr a diameter (Zr/c. a cross-section f/ and a specific resistance of which is assumed to be lo, then by baring` the wire alone' the edge O A, a sliding contact on, can be caused to rub alongy said edge and the variabli-f resistance i' ot thev rheostat thus itorined will be given by the formula:-

But if (lf/z is suliiciently sinall, it may be assumed that:-

1t l i Zijde fq/tl OB Lcos -midm By integration we get:

- i 1 Ey-dxf-GB- [sin :2r- @i ald).

the above formula will be reduced to zlt is to be noted further that, in order to teilte into consideration the thickness e ol the insulating strip and the diameter of the wire. the theoretical profile as above defi ied. inustbe corrected b v reducingT all the ordinates by the const-ant lengt-li:-

In Fifrures 2, 3 and 4:-

1 "2 esiena'tc the tcleineicr (Supported on collars L1 and L2 withA ball hearings) which can be adjusted to the site angle by rotatingA the hand wheel A.

C; a casino containinnvtlie rlieostats that gire the resistance l ll and El, This casing' is lifted io the. collars L and LI. andcan revolve arouno a vertical shaft r sui)- ported by a suitable footvll) B is a h:-.ntln'licel, by rot-ating;f which. the altimetcr operator is able to vary the resistance of the rheosiat .givingY K3 ll. It will be understood that hand u'hecl B is diagrammatic-ally illustrated in Figure l by the crank t".

The azimuth direction is obtainedby operatinf.,r the liandwhccls and l utilised as hand grips i'or the apparatus. l is a crank which enables the auxiliary operator to iel'urn the pointer oli the voltincter V to Zero by varying the. resistance of the rheostat that gives S.

F is a flexible shaft which ena-bles the rotation of u1 to he transmitted to the adjustine` knob ut of the telenieter.

g is a tivo-wire cable connecting the rheostats contained in C to the rheostat that gives K2 sin a, which is assumed to be mounted in the corrector.

I is a dial from which the distance D is read.

J is a dial from which the altitude H is read directly.

The adjustmentot the variable resistance K2 sin a is made in any suitable manner as, for example, by means Otan operator positioned at the corrector reterred to above. Adjustment of this resistance results in a dimlacement of the needle of the voltmetcr. This needle is then returned to zero position by the operator who actuates the crank ux and, simultaneously actuates the adjusting knob i114. beenreturned to zero position coincidence is not obtained in the t-elemeter. the telemeter opeiator actuates hand wheel B and further displaces the needle which is constantly ieturned to zero position by the operator actuating?r the cra-nk u1. It is in this manner that the telemeter operator controls the readings of the telen'ieter and the necessary coincidence.

For detcrniiiiing 'n'. the lVheatstone bridge may be substituted by any equivalent electro-mechanical mechanism. Only the following modification will be described by ivay of example It a constant voltage is available for feedincr a potentiometer. it is easy to obtain a voltage proportional to sin a (by constructing;r this potentiometer as hereinbetore indicated with respect to the rheostat giving K2 sin a) and causing` the pointer of a milliainperemeter to have a deflection proportional to the teleincter is then'ettected by recopying the deflection of the millampere-meter. or better still, by actingr upon the spiral spring;

It, when the voltnieter needle has a cainoid which can beslidden by the altimeter operator alongy the shaft 2 b v actuating the hand-wheel Il (which replaces the hand-Wheel B ol" Figures 2, 3 and 4). Thisl sliding' movement is produced by the screwV 4;, the nut 5 and the fork 6. The nut 5 carries a pointer 7 adapted to move over a graduated scale S from which the altitude H can be read ott. The shaft 2 is carried along in the site angle movements of the telemeter in such a manner as to malte one complete revolution when the site angle varies from 0 to 90.

I The rotation of the shaft 2 is transmitted to thev camoid l by a long key or Jfeather 9. Upon this cainoid l there bears the loiver end l0 of a vertical rod, the upper end of which carries a pointer 11. For a determined position ot the fork 6 that is to say for a determined value of the altitude ll the displacements ot the pointer l1 are rendered proportional to sin a by the outline of the corresponding right-angle cross-scction. et the eamoid.

`On the other hanch for a determined value of o: the displacements ot 1l are rendered inversely proportional to H by the outline of tlie corresponding axial section ot the camoid. The a'uxiliary operator maintains automatically the adjustment ot the telenieter by acting upon the screiv l2 (which replaces the screw u2 ot Figures l. 2 and 3 and et) connected to the adjusting knob, in such a manner as to bring7 opposite t0 l1, a pointer lf3 carried by the nut ll.

Figure G illustrates by nay of example. how the equation can be solved mechanically by balancingT a couple equal to K.L sin a by a couple lall produced by an ettort n acting through a leverage equal to H; the elgort n itself being obtained by displacing a constant Weight through a distance proportional to In this ligure: 2l is a weight attached to the end of a lever fixed to the internal toothed pinion Q2 that is loose on the shaft 23; 24 is al lever xed to the pinion that is loose on the shaft. Q3; QG is a pinion so arrant-ed to constitute a plane diilerentiai With 2Q and Q5; 2T is a lever movable around 2o and carrying the axle-pin oi 2G n-nfl i-nw-vvsinni-innr in n innl" Cnr-'truand ...o ew/i which meshes with a Worm 2:). T ie morements of the lever Q4; are limited by tivo fixed stops 3U and 31. The worin 29. being connected to' the operating site-angle" meehanism in such a nianncr that the lever carrying 2l will aluf'ays enclose with the vertical an anglo equal to ci, it is obvious that the couple transmitted to the lever '2l is proportional to' sin 1.

The equilibrium of the lever 2l is obtained by causing un upward vertical el'ort to come into action through the intermediary of the roller` 32. The roller 32 is mounted on the end of a leverk 325 a-dapted'to rock around the point oi suspension I- t which can be displaced by acting upon the hand crank 35 (which plays the same partas' the hand-wheel li of Figures i2', 3 and Ll) in s'uoli a manner that the distance between 32 and shall be proportional to H.1 The eort which is to be transmitted by SQ'Will, under these conditions, be proportional to n. This eitort is' produced by displacing the weight. 3G along the prolongation ot For this" purpose the auxiliary oi'ierator operates' the' hand crank 37' mounted on the screiv 38 (which replaces the screw u2 ot Figures l, 2,' 3 and l) connected to the adjusting knob' of` the telemeter, in such a manner so as to' bring the pointer 39, which is lixed to 24e',- opposite the fixed register mark '-10.'

'ihe invention will still remain? applicable when in addition to the altimeter operator, tvvo further operators are provided, namely, an operator having the duty of keeping the telemeter directed along the site angle by means' of a hand-Wheel such as A; with the help, in that case, of a' site-angle telescope mounted upon T1, T2. The second operator would have the duty of keeping the azimuth. For this p'urpose he Would have to operate the casing C and he would have a special telescope provided for his use; The altimeter operator would then only have to operate the hand-Wheel B ot4 Figures 2, 3' and sl (or the hand-Wheel 3 of Figure in order to follow anyv occurring variations in the altitude. oi the moving target.

W'hen it is desired to' employ the apparatus of the present invent-ion on board ivarships,v4 the entire apparatus may be mounted on al gyroscopicy support ot the type described in my application Serial No. 527,277 tiled January 5, 1922. ior installa# tion for tiring on board ivarships.

The invention is capable of receiving aY variety oi mechanical expressions, some of which have. been illustrated on the acompanving drawings but it. is to be expresslyY understood that the drawings are for purposes of illustration only and are not designed as a' definition' of ,the limits of the invention. 'The term telemeter as herein employed, is not. limited to monostatic telemcters of the coincidence type since itA includes other suitable types',` as for example,

a teleineter o the stereoscopic type. Reference' is therefore to be had to' the claims hereto appended'for a definition of the limits of the invention.

W hat l claim is y 1. An apparatus for measuring the altitude oi a. moving aerial targetcomprising supporting means, a teleme'ter mounted on the supportingmeans and having an adjusting member, a movable indicator carried by the supporting means, means -tor moving the indicator as a function of the sight anglo of the target, means for moving the indicator proportionally to the altitude of the target, and means operatively connected to said adjusting member for returning the indicator to normal position.

2. A device ot the class described comprising, in combination with a telemeter 3. A device of the class described compris'- ing in combination with av teleineter ot the coincidence type having an adjusting knob, a' voltmeter, ar plura"ty off resistirme-es connected to said voltmeter, a source of' current connected to the resistances and voltmeter, means for movingl the pointer ot the voltmeter in accordance with the variations in the angle of sight and altitude oi' the target and means operatively' connected to said adjusting knob for returningv said pointer to normal position,

l. A device oi the class described compris'- ing'in combination with a telemeter having an adjustingv member. a movable indicator, means for moving said indicator proportionally to the anglel oi sight of a target,A ineatns including a movable. pointer tor moving said indicator proportionally to the` altitude of the target, an altitude scale. positioned adjacent said pointer, means including a. movable pointer operatively connected to said adjusting member t'or returning said indicator to normal position. and a distance scale mounted adjacent said last named pointer.

5. ln combination. ay telemeter having an adjusting knob, Wlieatstone bridge comprising a plurality ot resistances and a voltneter, means for varying one ot said resistance-s as a function ot the angle of sight ot a target, means for varying another of said resistances in accordance with the altitude ot the target., the variation ot said resistances resulting in the deilection of the needle ot the voltmeter, and meansl operatively connected to said adjusting knob for varying another of said resistances whereby :1n-.l a fiexible member connected to said izisi named means and t0 said adjusting knob. Dated this 8th day of January, 1923. In testimony whereof I havesigned this specification.

EUGENE SCHNEIDER.

Witnesses ANDRE Nosricxnn, Louis GARDET. 

